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Articles 241 - 270 of 279
Full-Text Articles in Animal Sciences
Independent Acoustic Stimulation Of The Amphibian And Basilar Papillae Of Rana Pipiens, Mark Parker
Independent Acoustic Stimulation Of The Amphibian And Basilar Papillae Of Rana Pipiens, Mark Parker
Dissertations and Theses
This study attempted to selectively stimulate and record from either the amphibian or basilar papillae of Rana pipiens. Computer-generated, frequency-specific clicks were used to elicit BSER's from either amphibian or basilar papillae. Narrow-band noise fatiguers were presented in the frequency region of which each papillae are tuned. It was expected that a threshold shift would be elicited in the papillae that received the acoustic trauma, and that no threshold shift would be observed from the collateral papilla.
The results of this experiment indicated that there was no overall difference between the threshold shift of either papilla. Furthermore, the amount …
Breeding Patterns Of Eastern Phoebes In Kansas: Adaptive Strategies Or Physiological Constraint?, Michael T. Murphy
Breeding Patterns Of Eastern Phoebes In Kansas: Adaptive Strategies Or Physiological Constraint?, Michael T. Murphy
Biology Faculty Publications and Presentations
Data were collected on annual (1980-1983) and seasonal (spring vs. summer) variation in reproduction by the double-brooded Eastern Phoebe (Sayornis phoebe) to test the proposal that phoebes modify reproductive patterns on a seasonal basis and switch from being brood survivalists in spring to brood reductionists in summer. Clutch size did not differ between spring and summer broods nor among years, but spring nests fledged one more nestling than summer nests. In 1981 breeding began earlier, eggs were larger, and nestlings grew faster than in all other years. Clutch size and egg mass within spring clutches increased seasonally. Egg mass was …
An Assessment Of Behavior Associated With Reproduction And Infant Caretaking In A Captive Family Group Of Saguinus Midas Midas, Melissa Elizabeth Martenson
An Assessment Of Behavior Associated With Reproduction And Infant Caretaking In A Captive Family Group Of Saguinus Midas Midas, Melissa Elizabeth Martenson
Dissertations and Theses
The present study gathered both general and specific information about the behavior of a captive family group of Saguinus midas midas [red-handed tamarins] housed at the Washington Park Zoo, Portland, Oregon, USA. Saquinus midas midas is a rarely studied species, and detailed information about the behavior of this species is virtually nonexistent. For this reason, this study collected information about both activity budgets and social grouping within this family group.
The primary focus of this study was, however, the socialization of captive juvenile tamarins with respect to several behaviors relevant to reproductive success among the Callitrichidae. The behaviors assessed were: …
Biogeography And Species Density Distributions Of Tasmanian Mammals, Jerry E. Bevers
Biogeography And Species Density Distributions Of Tasmanian Mammals, Jerry E. Bevers
Dissertations and Theses
Separated from mainland Australia by the Bass Strait, Tasmania has acted as an island preserve maintaining large populations of many mammalian species presently uncommon, rare, or extinct on mainland Australia.
There are few studies of Tasmanian mammal distributions. Recent distributional maps, based on information from surveys and mammal specimens, allowed for an investigation of the species density distributions of the terrestrial mammals of Tasmania. Compilation of species' distributional information into species density distributions provides an overview as to which areas may provide the most significant habitat for the greatest number of species; what geographic variations may influence species distributions; and …
Dna Fingerprinting Analysis Of Captive Asian Elephants, Elephas Maximas, Laura Louise Bischof
Dna Fingerprinting Analysis Of Captive Asian Elephants, Elephas Maximas, Laura Louise Bischof
Dissertations and Theses
This thesis examined the effectiveness of DNA fingerprinting analysis for paternity ascertainment and the establishment of relatedness of captive Asian elephants (Elephas maximas). Eighteen Asian elephants from three North American zoos were examined. Thirteen of these elephants were wild caught. Relationships between these elephants and the remaining elephants born in captivity were known.
Analysis Of Mitochondrial Dna Restriction Fragment Patterns In Killer Whales, Orcinus Orca, Tracy Alison Stevens
Analysis Of Mitochondrial Dna Restriction Fragment Patterns In Killer Whales, Orcinus Orca, Tracy Alison Stevens
Dissertations and Theses
The mitochondrial DNA restriction fragment patterns of killer whales (Orcinus orca) were investigated in order to determine the level of genetic differentiation that exists between killer whales from various geographic locations. Twenty one killer whales were examined, seventeen of which were captive killer whales that originated from the North Atlantic and Northeast Pacific Oceans. Two were captive-born animals and two were killer whales that stranded along the Northeast Pacific coast.
DNA was extracted from blood and/or tissue samples, cleaved with a variety of restriction endonucleases and the DNA fragments were separated by horizontal agarose gel electrophoresis. The DNA …
Seasonal Trailing Behavior And Corticosterone Levels In Male Red-Sided Garter Snakes (Thamnophis Sirtalis Parietalis), Pamela Kay Thinesen
Seasonal Trailing Behavior And Corticosterone Levels In Male Red-Sided Garter Snakes (Thamnophis Sirtalis Parietalis), Pamela Kay Thinesen
Dissertations and Theses
Mechanisms of how red-sided garter snakes (Thamnophis sirtalis parietalis) travel up to 18 km from summer feeding sites to hibernation dens are not understood. In this study, monthly and seasonal trailing behavior were investigated to determine whether red-sided garter snakes prefer to follow trails of snakes from the same den (den-mates) versus trails made by other conspecifics (non-den-mates). Snakes from five different hibernacula in Manitoba, Canada, were involved in the study. Eighteen were adults and 15 were subadults. Subadult red-sided garter snakes do not return to hibernacula until their second year of life, so their trailing behavior was of interest …
Gibbon Classification: The Issue Of Species And Subspecies, Erin Lee Osterud
Gibbon Classification: The Issue Of Species And Subspecies, Erin Lee Osterud
Dissertations and Theses
Gibbon classification at the species and subspecies levels has been hotly debated for the last 200 years. This thesis explores the reasons for this debate. Authorities agree that siamang, concolor, kloss and hoolock are species, while there is complete lack of agreement on lar, agile, moloch, Mueller's and pileated. The disagreement results from the use and emphasis of different character traits, and from debate on the occurrence and importance of gene flow.
The Impact Of Weather On Kingbird Foraging Behavior, Michael T. Murphy
The Impact Of Weather On Kingbird Foraging Behavior, Michael T. Murphy
Biology Faculty Publications and Presentations
Foraging data on Eastern Kingbirds (Tyrannus tyrannus) were collected during the early breeding season in eastern Kansas to test the hypothesis that foraging rate and other aspects of foraging behavior vary with weather. Foraging characteristics of five additional kingbird species were also examined to assess Fitzpatrick's (1980) generalization that kingbirds (Tyrannus spp.) are aerial hawking specialists. In Eastern Kingbirds, total foraging rate was independent of air temperature, cloud cover, wind speed, and time of day, but the rate of aerial hawking varied directly with air temperature and inversely with cloud cover (both P < 0.05). Effects of the two variables were additive. The percentage of foraging movements that were aerial hawks also increased with temperature and declined with cloud cover, and, hover-gleaning and perch-to-ground sallying were observed mainly during cloudy weather. Sally (i.e., foraging flight) distance correlated directly with perch height and air temperature, and large insects were captured almost exclusively in long upward or horizontal flights. I interpret these data to indicate that foraging behavior and the capture of large, flying insects depends on weather because of how it affects the activity of insect prey. Foraging data on kingbirds support Fitzpatrick's generalization, but the relative use of aerial hawking varies considerably among species. Resident Tropical Kingbirds( T. melancholicus) are the most specialized foragers, whereas the migrant and widely distributed Eastern Kingbird appears to be the most generalized. Certain habitats also appear to favor the use of particular foraging methods (e.g., outward striking in grasslands and perch-to-ground sallying in drier, open habitats).
Body Size, Nest Predation, And Reproductive Patterns In Brown Thrashers And Other Mimids, Michael T. Murphy, Robert C. Fleischer
Body Size, Nest Predation, And Reproductive Patterns In Brown Thrashers And Other Mimids, Michael T. Murphy, Robert C. Fleischer
Biology Faculty Publications and Presentations
We describe the breeding biology of Brown Thrashers (Toxostoma rufum) in Kansas, and combine this with data from other temperate-zone breeding Mimidae to characterize reproductive patterns in this group. Brown Thrashers produced clutches of 3 to 6 eggs, but clutches of 4 predominated. Most pairs raised 2 broods per year. Incubation required between 13 and 14 days, and hatching was usually asynchronous. Though sample size was small, asynchrony appeared to increase in frequency towards the end of the breeding season. Nestlings grew rapidly, and in 10 days or less most pre-fledgingg rowthw as completed. Young fledgedn ormallya t 11 days …
Body Size And Condition, Timing Of Breeding, And Aspects Of Egg Production In Eastern Kingbirds, Michael T. Murphy
Body Size And Condition, Timing Of Breeding, And Aspects Of Egg Production In Eastern Kingbirds, Michael T. Murphy
Biology Faculty Publications and Presentations
Variation in timing of breeding in Eastern Kingbirds (Tyrannus tyrannus) was correlated only weakly with external morphological characters, but was correlated positively and significantly with estimates of body size based on measurements of skeletons and muscle weights. Small females apparently held a reproductive advantage in being able to mobilize resources for reproduction before large females. Egg weight was independent of all measures of female size, but was directly and significantly (P = 0.03) correlated with standard flight muscle weight, a relative index of body condition. Egg size was thus a function more of female body condition than size. On average, …
Brood Parasitism Of Eastern Kingbirds By Brown-Headed Cowbirds, Michael T. Murphy
Brood Parasitism Of Eastern Kingbirds By Brown-Headed Cowbirds, Michael T. Murphy
Biology Faculty Publications and Presentations
Understanding why brood parasites lay eggs in the nests of hosts that reject eggs is hampered by insuf-ficient data on the frequency with which parasites lay in rejecter nests, and by ignorance of which in-dividuals practice this seemingly inappropriate be-havior. Parasitism rates of rejecters can be deter-mined only when host nests are observed during egg laying because most parasite eggs are rejected rapidly (e.g. Scott 1977). Even then, however, a certain per-centage of parasitized nests may go undetected. De-termining the selective value of host defense mech-anisms also depends on knowledge of the frequency of parasitism, and the amount of reproductive …
The Analysis And Use Of Methodologies For The Study Of The Diets Of Long-Eared Owls From Three Environments In North Central Oregon, John M. Barss
The Analysis And Use Of Methodologies For The Study Of The Diets Of Long-Eared Owls From Three Environments In North Central Oregon, John M. Barss
Dissertations and Theses
Part I of this study presents a procedure for standardization of pellet analysis methodologies which improves estimation of prey biomass and determines the number of pellets needed to estimate prey diversity indices. The procedure was developed to provide a simple, easily replicated methodology for the study of pellets which also retains maximal data recorded from pellet analysis. A sample size of ten Long-eared Owl pellets was found adequate to calculate diversity indices with no significant loss of accuracy when compared to total pellets recovered from beneath a roosting site. Analysis of the total sample of pellets from a specific roost …
A Phylokaryotypic Evaluation Of The Genus Tursiops (Family Delphinidae), Melissa Kay Estes
A Phylokaryotypic Evaluation Of The Genus Tursiops (Family Delphinidae), Melissa Kay Estes
Dissertations and Theses
In an attempt to correlate genetic data with possible species delineation, this study investigates the presence of chromosomal variants between the North Atlantic bottle nose dolphin, Tursiops truncatus, and the North Pacific bottle nose dolphin, T. gilli. Blood samples were obtained from oceanaria in the United States. Location of capture was correlated with karyotype to compare chromosome morphology with geographic range.
Effects Of Intraperitoneal And Intracerebral Injections Of Triiodothyronine On Temperature Selection In Fish, Dennis A. Grahn
Effects Of Intraperitoneal And Intracerebral Injections Of Triiodothyronine On Temperature Selection In Fish, Dennis A. Grahn
Dissertations and Theses
Goldfish (Carassius auratus) of 15-28g were maintained at 23 C and subsequently were intraperitoneally injected with saline (controls) and varying doses of Triiodothyronine (T3). Following the injection, the fish were placed in a thermal gradient and temperature selection and activity monitored for 30 min. There was no- significant difference between the responses of the experimental fish to the 2 different doses of T3. However, there was a significant difference in response between the experimental and control groups (P < 0.001). The decreased temperature selection occurred early in the test runs, while the increased activity began later. Larger goldfish (175-205g) received 0.5 μl intracerebral injections of 1.5-3.0 ng T3 in the anterior brainstem via an indwelling cannula injection system. These fish responded to the injections by …
Nest Success And Nesting Habits Of Eastern Kingbirds And Other Flycatchers, Michael T. Murphy
Nest Success And Nesting Habits Of Eastern Kingbirds And Other Flycatchers, Michael T. Murphy
Biology Faculty Publications and Presentations
Patterns of nest placement and its relationship to nest success in the Eastern Kingbird (Tyrannus tyrannus) were studied in populations breeding in New York and Kansas. Data were augmented with information on nest placement in other open-nesting tyrannids in order to examine the hypothesis that these flycatchers place their nests chiefly so as to conceal them from predators. Nesting success was significantly greater in New York than in Kansas but was relatively high in both populations, as is apparently true of North American breeding flycatchers in general. Geographic variation in nest placement in the Eastern Kingbird was relatively small and …
Clutch Size In The Eastern Kingbird: Factors Affecting Nestling Survival, Michael T. Murphy
Clutch Size In The Eastern Kingbird: Factors Affecting Nestling Survival, Michael T. Murphy
Biology Faculty Publications and Presentations
Observational and experimental procedures were used to evaluate the potential importance of brood size and weather on the evolution of clutch size in the Eastern Kingbird. Modal clutch size was three eggs, yet broods of four were most productive. Nestling size varied inversely with brood size, so that "nestling quality" was lower in broods of four than in broods of three. Asymptotic weight of nestlings in broods of three was directly and significantly correlated with ambient air temperature, followed by hatch order. Because larger broods were being fed during a period of relatively cool and wet weather, the effects of …
Breeding Success And Nest Site Characteristics Of The Western Bluebird On Parrett Mountain, Marcia Diane Sims
Breeding Success And Nest Site Characteristics Of The Western Bluebird On Parrett Mountain, Marcia Diane Sims
Dissertations and Theses
The lack of suitable nest sites may be a limiting factor for Western Bluebird populations inhabiting the upper Willamette Valley. Nest box trails have been established on the hills surrounding the Portland metropolitan area. Since their placement, approximately 25% of the boxes available have been used by Western Bluebirds as nest cavities. This study was undertaken to identify factors which might determine the selection of a nest box by Western Bluebirds and the subsequent nest success or failure.
The breeding biology of Western Bluebirds using the nest box trail located on Parrett Mountain, Oregon in 1979 was investigated. Breeding season, …
Anuran Activity Energetics, Scott R. Landrey
Anuran Activity Energetics, Scott R. Landrey
Dissertations and Theses
This thesis presents two separate experiments concerning aerobic and anaerobic amphibian energetics. The first study (Part I) investigates differential alterations in the kinetics of the anaerobic enzyme lactate dehydrogenase, in nine species of anurans with varying natural histories. The second study (Part II) studies changes in different anaerobic and aerobic physiological parameters in a single species (Rana catesbeiana) after six weeks of chronic exercised, unexercised-captive and for field frogs. The common theme of these two experiments involves the potential for physiological changes due to environmental stress. Part I examines different species to infer a possible evolutionary relationship to …
Factors Affecting Thyrotropin Secretion In Superfused Rat Anterior Pituitary Cells, Frederick Scott Bartlow
Factors Affecting Thyrotropin Secretion In Superfused Rat Anterior Pituitary Cells, Frederick Scott Bartlow
Dissertations and Theses
The use of static in vitro pituitary cultures has been indispensible for examining the regulation of anterior pituitary hormone secretion. While the static cultures have shown the effects of various chemical stimulators of hormone secretion, the dynamics of such secretion has not been assessed before in vitro. The in vitro superfusion method, which partially stimulates in vivo physiologic conditions, allows for the observation of the dynamics of pituitary hormone secretion.
Temporal And Phenomenological Aspects Of Social Behavior In Captive Wolves (Canis Lupus L.), Paul C. Paquet
Temporal And Phenomenological Aspects Of Social Behavior In Captive Wolves (Canis Lupus L.), Paul C. Paquet
Dissertations and Theses
Although cooperative behavior is generally acknowledged to occur among wolves, there is a lack of systematically collected data confirming the extent of development. The objectives of this study were to collect long-term, detailed observations documenting the role of social structure, seasonal influences, and individual participation in wolf pack cooperative activities. Individual cooperative strategies were associated with age, sex, and social positions and critically compared with results of similar studies. Emphasis was placed on quantifying group and dyadic relationships, focusing on reproductive strategies and dominance structure. Additional data were collected on denning behavior, maternal care behavior, scent marking, and spontaneous individual …
The Red-Tailed Hawk On Sauvie Island, Oregon, Kevin J. Lien
The Red-Tailed Hawk On Sauvie Island, Oregon, Kevin J. Lien
Dissertations and Theses
A study was undertaken to determine the abundance, distribution, perching heights, diets and territory sizes of Red-Tailed Hawks on Sauvie Island, Oregon. Sauvie Island supported a large wintering population of non-territorial Red-Tailed Hawks. The establishment of territories began around 10 January. Average perch height was found to be 14.2 m. Average perch height increased from fall to spring, corresponding-to the onset of the breeding season and to the onset of egg-laying and incubation. Voles (Microtus spp.) were the principal prey year-round, though waterfowl were more important in terms of biomass in the winter and early spring. Territory sizes on the …
The Metabolic Cost Of Behavioral Thermoregulation Of Body Temperature In The Northern Alligator Lizard Gerrhonotus Coeruleus, And How It Affects The Classical Concept Of Eurythermality, James Dudley Campbell
The Metabolic Cost Of Behavioral Thermoregulation Of Body Temperature In The Northern Alligator Lizard Gerrhonotus Coeruleus, And How It Affects The Classical Concept Of Eurythermality, James Dudley Campbell
Dissertations and Theses
The effect of total metabolic cost expenditures on the precision of behavioral thermoregulation was investigated for the purportedly eurythermic Northern Alligator lizard (Gerrhonotus coeruleus). An operant apparatus was designed to test metabolic output at different heat reinforcement magnitudes. The mean TB reflected in each trial was positively correlated to the length of reinforcement. The shuttle rate during each trial was inversely correlated to the length of reinforcement. The standard deviation and total metabolic costs did not vary significantly between trials undertaken at the same ambient temperature. Eurythermality in G. coeruleus is caused by fluctuations in preferred body temperature and …
Revetment Clearing, Its Influence On Riparian Mammal Communities, Robert E. Willis
Revetment Clearing, Its Influence On Riparian Mammal Communities, Robert E. Willis
Dissertations and Theses
Over 115 miles of rock revetment have been constructed in the Willamette Basin to protect river banks. This study examines the effect on riparian mammals of maintaining these revetments by vegetation and debris clearing. Differences between cleared and uncleared revetments were measured using a canopy coverage method of vegetation analysis; mammals were studied by trapping, by direct observation, and by noting such signs as scats, tracks, etc.
The Effect Of Developmental Temperature On Morphology, Energy Metabolism, Growth Hormone And Thyroid Stimulating Hormone In Long-Evans Rats, Dana Elizabeth Quinn
The Effect Of Developmental Temperature On Morphology, Energy Metabolism, Growth Hormone And Thyroid Stimulating Hormone In Long-Evans Rats, Dana Elizabeth Quinn
Dissertations and Theses
Long-Evans rats were raised from birth to eight weeks of age at 5°C, 20°C and 30°C. Blood was taken from animals two to eight weeks of age and assayed for growth hormone and thyroid stimulating hormone. The 30°C reared rats were found to have the longest ear, tail and hind limbs, followed by the 20°C reared rats. The 5°C rats were found to have the shortest ear, tail and hind limb. The 30°C and 5°C reared rats were found to have similar masses at the termination of the experiment. The 20°C reared rats had the smallest mass. Differences in size …
Social Behavior In A Group Of Captive Bobcats : A Study In The Sociability Of Felids, Lon W. House
Social Behavior In A Group Of Captive Bobcats : A Study In The Sociability Of Felids, Lon W. House
Dissertations and Theses
A group of four captive bobcats (Felis rufus), two males and two females, was observed for 102.67 hours over the period of one year. A pilot study was conducted consisting of a minimum of three separate observations for each daylight hour. The remaining observations were concentrated during the early morning hours immediately after feeding, the time of maximum activity and social interaction.
Distribution And Ecology Of Great Blue Heron Colonies On The Willamette River, Oregon, Scott M. English
Distribution And Ecology Of Great Blue Heron Colonies On The Willamette River, Oregon, Scott M. English
Geography Faculty Publications and Presentations
In the United States there is breeding ecology information available on the Great Blue Heron (Ardea herodias), but large-scale distributional and productivity information is lacking. In the lake regions of the Canadian provinces of Alberta, Manitoba, and Saskatchewan, regional surveys of Great Blue Heron nesting sites have been done by Vermeer and Reynolds (1970) and Vermeer (1969). Breeding biology studies were done in California (Pratt 1970, Page 1971), Canada (Vermeer 1969, McAloney 1973), and Oregon (Henny and Bethers 1971). In 1974 a survey of Great Blue Heron heronries on the Oregon Coast was completed through a National Science …
Bird Use Of Revetted Riverbanks In The Willamette Valley, Clifford Brian Perry
Bird Use Of Revetted Riverbanks In The Willamette Valley, Clifford Brian Perry
Dissertations and Theses
Over 115 miles of rock revetments that serve to protect river banks have been constructed in the Willamette Basin. In this study the spring and summer bird use of Willamette Basin revetments is examined. Revetments that had not been recently cleared of most woody vegetation and blackberries were found to have significantly greater total and breeding bird use than cleared revetments. Possible factors affecting bird use, such as vegetation on revetments and vegetation adjacent to revetments are examined using linear regression analysis. The results of this study are compared with results of previous work in riparian forests along the Columbia …
Distribution And Behavior Study Of Diurnal Tree Squirrels In Portland, Oregon, With Emphasis On The Western Gray Squirrel (Sciurus Griseus Griseus Ord) And The Western Fox Squirrel (S. Niger Rufiventer E. Geoffroy St.-Hilaire), Ira Young Rice Iii
Dissertations and Theses
Populations of diurnal tree squirrels in the Portland area were located by mail surveys, personal interviews, and field inspections. Pine squirrels were found to reside in thickly wooded residential areas with dense understories and running water nearby. Western gray squirrels occupied habitats in relatively quiet residential neighborhoods, in areas well supplied with mast crops. Western fox squirrels were found to coexist with gray squirrels in their preferred habitat, and also to thrive in park settings with few mast trees and high activity and noise levels. In areas occupied by both fox and gray squirrels, dominant-subordinate relationships were noted. Each species …
Bat Homing, John Mark Perkins
Bat Homing, John Mark Perkins
Dissertations and Theses
A model proposed by Wilson & Findley (1972) to test for randomness in bat homing was applied to results of homing studies on big brown bats (Eptesticus fuscus) and, when possible, to published studies on homing by other bats.
Most applications of the model suggest randomness in bat homing. Ecological notes concerning parturition, parasites, populations, emergence time, flight behavior and morphology of the E. Fuescus colony are reported.